A group of minerals whose chemical compound consists of a halogen with a more electropositive element or group
A group of minerals whose chemical compound consists of a halogen with a more electropositive element or group
Term used to describe a radioisotopes decay to 50% of its current energy
Said of rocks with a jagged or fractured surface
A general term used to describe a rock by its surficial appearance including crystal form
A retaining wall at one or both ends of a culvert structure
The steel, concrete or timber frame at the top of a shaft usually rigged to support hoist cables
Mining solid ore by drilling, blasting, milling and eventually refinement of minerals generally not emplaced by any glacial activity or erosion
Mining solid ore by drilling, blasting, milling and eventually refinement of minerals generally not emplaced by any glacial activity or erosion
Relatively small scale mining, usually performed for exploration purposes, utilizing hand tools such as picks, shovels, sluices, goldpans and not powered equipment
A milling machine that utilizes a series of revolving hammers to pulverize falling rock led through a chute